The present invention relates to apparatus for transporting and guiding tools or analogous implements in machines for the processing of tobacco or related commodities, for example, in machines for the manufacture and/or treatment of rod-shaped articles which constitute or form part of smokers' products. Such articles include plain or filter tipped cigarettes, cigarillos or cigars, filter rod sections as well as continuous tobacco-containing rods or filter rods. More particularly, the invention relates to improvements in apparatus of the type wherein tools or like implements are transported along endless paths and in such a way that the orientation of the tools remains unchanged during each and every stage of each cycle.
Commonly owned German Offenlegungsschrift No. 1,632,213 discloses an apparatus wherein two carriers are rotatable about parallel axes and are coupled to each other by several crank units which insure that the orientation of tools which are mounted on one of the carriers remains unchanged while the carriers rotate in response to transmission of torque to the one or the other carrier. The positions of tools are fixed by means of crank units. The German publication further discloses that the tools can be used for transfer of rod-shaped smokers' products between a first conveyor wherein or whereon the articles move sideways and a second conveyor wherein or whereon the articles move lengthwise. The spacing between the centers of neighboring articles remains unchanged. Each tool or implement is a holder which is formed with a flute and with suction ports serving to attract an article to and to retain the attracted article in the respective flute during transfer from the first conveyor to the second conveyor or vice versa. The German publication also discloses that the apparatus which is described therein can serve as part of a mechanism (known as cutoff) which severs a continuous rod containing a rod-like filler of tobacco and/or filter material and a tubular wrapper of cigarette paper, artifical cork or like material which surrounds the filler. The tools which are carried by the apparatus constitute tubular guides each of which has a slot and which serve to guide the rod in the region where, and at the time when, the rod is severed by a rotary knife. The knife extends into the slot of a tubular guide while its cutting edge severs the rod.
The apparatus of the German publication transports the tools along an endless circular path wherein the tools are transported at a constant speed. This reduces the versatility of the apparatus. For example, it is customary and desirable to change the distance between the centers of neighboring rod-shaped articles when a single file of closely adjacent or abutting coaxial articles is converted into a row wherein the articles move sideways. As a rule, the articles of the row are closely adjacent to each other. Examples of such articles are plain cigarettes which issue from a cigarette maker in the form of a single file of discrete articles of unit length and are to be converted into a row of articles which move sideways into and in a filter tipping machine. When the file is converted into a row by resorting to the apparatus of the aforementioned German publication, such apparatus must be followed or preceded by a conveyor which changes the spacing between neighboring cigarettes of the row or file.
When the apparatus of the German publication is used as a means for supporting the aforementioned tubular guides in the cutoff of a machine wherein a continuous rod is subdivided into a file of discrete rod-shaped articles or sections, the speed of a tubular guide, as considered in the longitudinal direction of the rod, matches the speed of axial movement of the rod only at the location where the rod is tangential to the circular path of the tubular guides. Therefore, such apparatus cannot be used (or are impractical) in machines wherein a succession of rod-shaped articles must be placed one behind the other in order to form a continuous rod-like filler or the like. Fillers consisting of a single file of coaxial rod-shaped articles are formed in machines which are utilized for the production of so-called multiplex filter plugs, namely, filter mouthpieces each of which contains two or more rod-like components consisting of different filter materials. The rod-shaped articles which are about to be deposited behind the last article of the rod-like filler are likely to interfere with transport of the preceding articles or vice versa. This will be readily appreciated by bearing in mind that a row of rod-shaped articles which move sideways can be converted into a single file, wherein the articles are immediately adjacent to and coaxial with each other, only if the distance between the axes of the neighboring articles in the row equals the length of an article. If the articles which move sideways are closely adjacent to each other, interference due to clashing between successive rod-shaped articles which approach or are about to enter the path for the single file of articles is unavoidable because each such article has a component of movement in as well as a component of movement at right angles to the direction of movement of the file to the very moment when the article assumes the position of coaxiality with preceding articles of the file.
Attempts to overcome the just discussed drawbacks of the apparatus of the German publication, when such apparatus is used for transfer of successive rod-shaped articles or groups of articles which form a row into a path wherein the articles form a single file and are immediately adjacent to each other, include the utilization of conveyors which move the articles sideways and are provided with widely spaced-apart flutes for the articles as well as the utilization of drive means which effect pronounced acceleration of articles during transport toward the path for the single file of articles. Such attempts have met with limited success, partly due to higher cost and partly because the apparatus are too complex and require frequent attention and extensive maintenance.
Limited versatility of the apparatus which is disclosed in the German publication renders it necessary to replace such apparatus with, or to utilize instead of such apparatus, machines or devices which are complex, prone to malfunction, very expensive and, at least in several important respects, less satisfactory than the apparatus of the German publication.